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Line 1: − [[Image:Atoms1.jpg|thumb|right|Subatomic resolution of atoms by AFM]]+ − An '''atom''' is+ − + − The word atom comes from the Greek term for indivisible, ''átomos''. − ===Structure===+ − Atoms are comprised of three subatomic particles: positively charged [[proton]]s, electrically neutral [[neutron]]s and negatively charged [[electron]]s. Protons and neutrons are comprised of quarks and are contained in close proximity in the center of an atom, forming the [[nucleus]]. Electrons inhabit the space around the nucleus, and are arranged around it in a series of layers, known as [[electron shell|shells]] or energy levels. − Currently quarks and electrons are considered truly elementary particles, though neither are capable of being seen. − Those who understand electrical theory might notice that positively charged particles packed closely together would repel one another. The nucleus stays together because of what is known as the ''strong nuclear force''. The quantization of this force is a tiny particle called a "gluon". + − ===Atomic Number=== − [[Image:Isotopes.jpg|righ|thumb|Isotopes]] − Chemical elements are made up of atoms with certain properties. The number of protons in the nucleus of an atom (known as the [[atomic number]]) determine the properties of the atom, and the element it constitutes. For example, [[Hydrogen]] has one proton, and therefore an atomic number of 1. [[Oxygen]] has 8 protons in its nucleus and has an atomic number of 8. Under normal conditions, atoms contain an equal number of protons and electrons. − ===Ions===+ − Atoms are normally electrically neutral; they have no charge. However, electrons in the [[valence shell]] can be gained or lost (depending on the element and the conditions) to form an [[ion]]. An atom that loses electrons becomes positively charged and is known as a cation. An atom that gains electrons electrons becomes negatively charged and is known as an anion.+ − Many common substances are made up of ions. For example, [[sodium chloride]] (NaCl), otherwise known as table salt, is made up of [[sodium cations]] (Na<sup>+</sup>) and [[chlorine]] anions (Cl<sup>-</sup>) in equal proportions. The negatively charged chlorine ions are attracted to the positively charged sodium ions, forming an [[ionic bond]]. This results in a lattice structure, which is responsible for sodium chloride being crystalline in its solid state.+ − ===Isotopes===+ − Atoms of the same element that have different numbers of neutrons are known as [[isotope|isotopes]]. Some isotopes are more stable than others, and occur more often in nature, but there is no "standard" number of neutrons in a given element. The atomic weight of an element is a weighted average of the number of neutrons and protons (number of protons remains constant in a given element) in all naturally occurring isotopes.+ − [[Category:Chemistry]] − [[Category:Physics]] − ==References==+ − <references />+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
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Come on Conservapedia! You're looking more ridiculous than usual by not reporting this! You've reported on pretty much everything else about Iran, so why not the fact that BUSH LIED TO US!?!?!?!?!!?
WASHINGTON - First Iraq, now Iran. The United States has operated under a cloud of faulty intelligence in both countries.
a [[particle]] of [[matter]] indivisible by [[chemical]] means. <ref>[http://www.lbl.gov/abc/Glossary.html Glossary of Nuclear Terms] </ref>
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In a bombshell intelligence assessment, the United States has backed away from its once-ironclad assertion that Tehran is intent on building nuclear bombs.
Where there once was certainty, there now is doubt. "We do not know whether it currently intends to develop nuclear weapons," the new estimate said Monday.
Compare that with what then-National Intelligence Director John Negroponte told Congress in January. "Our assessment is that Tehran is determined to develop nuclear weapons."
Just last month, President Bush, at a news conference with French President Nicolas Sarkozy, said, "We talked about Iran and the desire to work jointly to convince the Iranian regime to give up their nuclear weapons ambitions, for the sake of peace."
More ominously, Bush told a news conference Oct. 17, "I've told people that if you're interested in avoiding World War III, it seems like you ought to be interested in preventing them from having the knowledge necessary to make a nuclear weapon."
Asked then if he definitely believed that Iran wanted to build a nuclear bomb, Bush said, "Yeah, I believe they want to have the capacity, the knowledge, in order to make a nuclear weapon."
Bush's National Security Adviser Stephen Hadley said the president made comments like those "because he was describing the threat as the intelligence community itself had been describing the threat both publicly and in their briefings to him."
Intelligence officials advised Bush several months ago that they were reevaluating their assessments about Iran. They came to the White House last Wednesday and briefed him on their new findings.
The intelligence flip-flop recalled the embarrassing reversal that Bush was forced to make on whether Iraq possessed weapons of mass destruction. The conviction that Saddam Hussein had such weapons was one of the factors behind Bush's decision to invade Iraq. It since has been determined that Iraq did not have weapons of mass destruction.
Democrats on Monday did not hesitate to suggest an Iran-Iraq comparison.
Senate Majority Leader Harry Reid said Democrats had requested the new Iran assessment "so that the administration could not rush this Congress and the country to another war based on flawed intelligence."
"I hope this administration reads this report carefully and appropriately adjusts its rhetoric and policy vis-a-vis Iran," Reid said. "The administration should begin this process by finally undertaking a diplomatic surge necessary to effectively address the challenges posed by Iran."
In the case of Iran, though, the White House has not dropped its suspicions that Tehran could pursue a nuclear bomb.
Iran continues to develop, test and deploy ballistic missiles, and its civilian uranium enrichment program is continuing. "It can readily use the same technology to produce weapons-grade uranium," Hadley said.
In rewriting the conclusions about Iran, the new estimate said Tehran was pursuing a nuclear weapons program but halted that effort in the fall of 2003 under the weight of international pressure. Importantly, the estimate said Iran has not restarted the nuclear bomb program.
"Tehran's decision to halt its nuclear weapons program suggests it is less determined to develop nuclear weapons than we have been judging since 2005," the new estimate said.
While key facts have changed, the administration's strategy has not.
The White House says it will continue to try to build pressure on Iran to prevent it from ever acquiring nuclear bombs.
"The bottom line is that for that strategy to succeed, the international community has to turn up the pressure on Iran with diplomatic isolation, United Nations sanctions and with other financial pressure," Hadley said. "And Iran has to decide that it wants to negotiate a solution."
Some analysts believe the new conclusions will be a roadblock for Vice President Dick Cheney and other hawkish members of the administration to be more confrontational toward Iran.
"It's a good thing that we caught this before we marched headlong into another military conflict," said Jon Wolfsthal, senior fellow at the Center for Strategic and International Studies in Washington. "This isn't the timebomb the administration made it out to be for the last several years."
Wolfsthal said the conclusion that international pressure prompted Iran to halt its program "is the piece of information that we missed in Iraq" where Bush believed that Iraq's pursuit of WMD was continuing despite sanctions. He said the administration did not appear inclined to change its strategy toward Iran. He said that "suggests they can't take yes for an answer."
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EDITOR'S NOTE — Terence Hunt has covered the White House for The Associated Press since the Reagan administration.